PubMed Health⌕ Search

Biomedical subjects

RS Schwartz

Publications and source records attributed to RS Schwartz.

7 recordsLinked to original sources
PubMed2000

Bypass Without the Surgeon: The Coronary Veins as Arterial Conduits.

More than a century ago, Pratt demonstrated that perfusion of arterial blood through the coronary veins could sustain myocardial viability during acute ischemia. Recognition that atherosclerosis spared the coronary veins and that these vessels frequently followed a parallel course to the corresponding artery provided the necessary stimulus for the development and evaluation of several methods of venous retroperfusion. Although most of these procedures have now been superseded, the coronary veins remain a tempting therapeutic target when direct arterial revascularization is not feasible. Novel percutaneous strategies using these vessels to provide definitive myocardial revascularization have been proposed and extensively tested in animals.

Journal Article↗
PubMed2000

The Coronary Venous System: An Alternate Portal to the Myocardium for Diagnostic and Therapeutic Procedures in Invasive Cardiology.

Retrograde coronary venous perfusion can preserve myocardium during experimental coronary artery occlusion and has been used clinically to deliver oxygenated blood to ischemic myocardium during unstable angina or high-risk percutaneous transluminal coronary angioplasty (PTCA). Retrograde delivery of drugs accelerates coronary thrombolysis, preserves regional myocardial function, and limits infarct size in animal models. Modifications of the coronary venous retroperfusion technique have allowed access to smaller coronary venous branches and minimization of systemic effects of local drug delivery. Retrograde coronary sinus perfusion as an adjunct in high-risk coronary PTCA is limited by its inability to provide systemic hemodynamic support during circulatory collapse. Targeted and specific gene delivery to myocardium with transfection rates superior to intraarterial or systemic injection may be a promising new application for this technique. The coronary venous system can also be used for the noninvasive creation of coronary artery bypasses or the insertion of leads for left ventricular pacing. Contrast-enhanced electron beam computed tomography (EBCT) can noninvasively provide high-resolution imaging of the coronary vessels with qualitative and quantitative information on coronary venous anatomy and coronary arteriovenous relationships and may help in selecting appropriate candidates, anticipating the degree of difficulty of the procedure, and guiding the approach. Therefore, EBCT may become the imaging modality of choice for the assessment of patients considered for such strategies.

Journal Article↗
PubMed2000

Restenosis and Hyperplasia: Animal Models.

Coronary restenosis after percutaneous interventions remains a major clinical problem even in the days of coronary stents. Understanding the pathophysiologic mechanisms and the assessment of therapies for the prevention of restenosis relies on experimental animal models. This article describes the most frequently used animal models of coronary artery restenosis and the differences among them. The variable response to injury in the different models should be considered in the interpretation of the effective therapies before they are transferred into clinical trials. The rat carotid model played an important role as a pioneer in animal models for restenosis but has failed to predict results of clinical restenosis. This lack of predictability highlights a fundamental lack of understanding of the basic molecular mechanisms that control vascular healing after injury.

Journal Article↗